1. Field of the Invention
The invention relates to a discontinuous linear drive comprising a guiding component and an engaging means which drives forward an element guided by the guiding means.
2. Discussion of the Prior Art
From prior art, for instance according to DE-OS 39 25 484 of the applicants themselves, a discontinuous drive of this species is known. In said drive two axially spaced support members are provided in the form of radially expandable supporting rings which are coupled to each other via a sleeve-shaped spacer. The spacer is mainly formed by a piezoelectric element or hydraulically operable bellows which, accordingly, are variable in their axial length.
For a progressive movement it is provided to alternately radially expand the two supporting rings and contract them again and, in so doing, to push forward the supporting ring which is currently not supported or rather pull it along by expanding or contracting the spacer. Such a linear drive pulls a load or a component to be conveyed for instance into a tubular cavity, the axial supporting rings being supported on the inside of the cavity wall.
Although in this way a controlled progressive movement is possible, the known discontinuous linear drive requires an external support, for instance the afore-mentioned cavity wall, so that the use thereof is not always possible or, rather, can take place only after expensive conversion measures and adaptations to the spatial circumstances.
Therefore, the invention is based on the object to provide an improved and cost-effective linear drive of this species.